In telecommunications networks, routers and switches are used to direct data packets from a data packet's origin to its destination. Often a router or switch will have multiple incoming and outgoing transmission lines (or “ports”). Therefore, to route a packet through a telecommunications network, it is necessary to properly internally route the data packet at each router or switch from the incoming transmission port to the proper outgoing transmission port. This is commonly achieved by classifying the packets at the ingress edge of the switch/router. This classification of data packets can include determining the egress edge unit of the switch/router to which a particular data package should be routed. In this manner, data packets can be switched from a particular incoming transmission port to a particular outgoing transmission port through the switch/router.
In current data packet classification and routing systems, a data packet arrives at an ingress interface unit of a router where packet classification occurs. During packet classification, current systems will classify the data packet based on its destination port, which is associated with a particular egress edge unit. According to the classification, the router will route the data packet to the appropriate egress edge unit of the optical network for further routing. In current optical networks, however, the classification of a data packet is typically not retained once the data packet leaves the ingress edge unit in route to the egress edge unit.
In operation, data packets are classified in current systems and methods for classifying data packets based on the destination egress edge unit. When a packet arrives at the destination egress edge unit, classification is repeated to determine the destination egress interface port of the egress edge unit. Thus, the processing to determine the destination occurs in two stages. First it occurs at the ingress edge unit to determine to which egress edge unit a data package is bound and, again, at the egress edge unit to determine to which egress interface port the data package should be routed. Because classification occurs both at the ingress edge unit and the egress edge unit, current optical networks require that there be classification hardware at both units.
As noted, prior art packet classification systems and methods require repeating the classification process at the egress edge interface unit. Therefore, a need exists for a packet classification system and a method that can perform the classification only at the ingress edge unit, thus reducing the complexity and computational requirements at the egress edge unit.